Piston makes OpenStack software for so-called "private clouds" that companies use in their data centers. OpenStack is open-source software used by some of Amazon's biggest competitors, including Rackspace and HP.

Competitor Rackspace was more gracious. It merely pointed out the outage to its customers by tweeting on @Rackspace, "We wish our friends at AWS and all of their customers the best. Everyone suffers down-time and never at a good time."

Everyone was talking about the irony of the outage, too. It happened on the same day that Amazon said it was cutting prices on customer support in a blog post titled, "AWS Support - We've Got Your Back."

In that post, Amazon boasted about all the things Amazon was doing to make sure its cloud doesn't fail.